Mark Williams, PNHNP-BC
NPI 1639847049 · Psychiatric/Mental Health Nurse Practitioner · Reno, NV
Enrolled with Medicare as Practitioner - Nurse Practitioner · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Mark Williams, PNHNP-BC is a Psychiatric/Mental Health Nurse Practitioner provider in Reno, NV (NPI 1639847049).
Provider details
- NPI number
- 1639847049
- Entity type
- Individual
- Primary specialty
- Psychiatric/Mental Health Nurse PractitionerPhysician Assistants & Advanced Practice Nursing Providers
- Credential
- PNHNP-BC
- Sex
- Male
- Sole proprietor
- No
- License
- 836585 (NV)
Specialties & taxonomies
Physician Assistants & Advanced Practice Nursing Providers
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
4 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
2 documented practice locations
- Medicare service volume (vs. specialty peers)28% of score
110 Medicare services, 2024 (ranked within specialty)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 35 Minutes99232 | 82 | $65 |
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 50 Minutes99233 | 28 | $97 |
Typical Medicare-allowed amounts for these services range $65–$97 (2024). The Medicare-allowed amount is what Medicare recognizes for a service under fee-for-service — a reference figure for 2024, not a price quote and not what you would be billed. Medicare Part B covers roughly an eighth of all NPIs (65+ skew); services with fewer than 11 beneficiaries are suppressed by CMS. Source: CMS Medicare Physician & Other Practitioners, by Provider & Service.
Practice location
Mailing address
Additional practice locations (1)
- 975 Kirman AveReno, NV 89502-0993Phone: (775) 636-2699
Registry dates
- Enumerated
- 2021-08-31
- Last updated
- 2024-07-09
- Certified
- 2024-07-09
Frequently asked questions
- What is Mark Williams's NPI number?
- Mark Williams's National Provider Identifier (NPI) is 1639847049, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Mark Williams's specialty?
- Mark Williams is listed in the NPPES registry with a primary specialty of Psychiatric/Mental Health Nurse Practitioner (Physician Assistants & Advanced Practice Nursing Providers).
- Where is Mark Williams located?
- Mark Williams's practice location on file with NPPES is 1155 Mill St, Reno, NV 89502-1576.
- What is Mark Williams's phone number?
- The practice phone number listed in the NPPES registry for Mark Williams is (775) 982-2860.
- Does Mark Williams accept Medicare?
- Mark Williams is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Mark Williams's NPI active?
- Yes — Mark Williams's NPI (1639847049) is active in the NPPES registry as of the last update on 2024-07-09.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.